Electronic devices such as tablet laptop computers and portable information terminals have recently been becoming mounted with touch panels (touch screen sensing modules) for the purpose of enhancing operability and usability. A known example of a touch panel is disclosed in Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2015-509255. A touch screen sensing module disclosed in Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2015-509255 includes a first base plate, a first conductive layer, a second base plate, a second conductive layer, and a support substrate. A first groove of a predetermined shape is defined on one side of the first base plate. The first conductive layer is shaped in conformance with the first groove, and the first conductive layer is accommodated in the first groove. A second groove of a predetermined shape is defined on one side of the second base plate. The second conductive layer is shaped in conformance with the second groove, and the second conductive layer is accommodated in the second groove. The first conductive layer and the second conductive layer are shaped in conformance with the first groove and the second groove, respectively. This eliminates the need for etching to obtain an electrode in forming a conductive layer, thus making it possible to avoid wasting materials and reduce costs.
In the touch screen sensing module disclosed in Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2015-509255, a first electrode lead wire is formed in the same first groove as the first conductive layer, and a second lead wire is formed in the same second groove as the second conductive layer. That is, since the first electrode lead wire and the second electrode lead wire are placed on the first base plate and the second base plate, respectively, a design needs to be made with such consideration that the first electrode lead wire placed on a lower level is not covered by the second base plate placed on an upper level. For this reason, the ranges of placement of the first electrode lead wire and the second electrode lead wire tend to be so wide that a frame width is great. Further, the difference in level between the first electrode lead wire and the second electrode lead wire makes it difficult to mount an external component that is connected to the first electrode lead wire and the second electrode lead wire.